The present invention relates to a cable connector which is able to be connected to a plurality of balanced transmission cables.
The balanced transmission cable comprises a pair of signal conductors, an insulating member and an electrical shield such as a braided metal shield. The signal conductors constituting one pair are insulated from each other by the insulating member. The electrical shield surrounds the insulating member and serves as common ground to the pair of signal conductors when being electrically connected to a ground point of an objective circuit.
JP-A 2000-68007 discloses a cable connector which is able to be connected to the balanced transmission cables. Usually, a plurality of balanced transmission cables are equi-angularly spaced around an central insulator core and are sheathed in an outer insulator jacket to form a cable assembly. The cable connector comprises a plurality of signal contacts, a plurality of ground contacts, and a supplementary substrate. On the supplementary substrate, a plurality of signal pads, a plurality of ground pads and two ground lands are formed. The signal pads are connected to the respective signal contacts, while the ground pads are connected to the respective ground contacts. The ground contacts are grouped into two groups, each of which is also connected to the corresponding ground land. When the balanced transmission cables are connected to the cable connector, they are separated to each other by skinning off the jacket and the electrical shields of the cables are soldered on the respective ground land. The paired signal conductors of each cable are separated by removing the braided metal shield, exposed by skinning off the insulator therebetween and soldered on the respective signal pads.
In the cable connector disclosed in JP-A 2000-68007, each of cables and each of signal conductors are not always soldered at fixed positions on the ground land and the signal pads. Further, they are left loose except portions soldered to the ground land the signal pads. Therefore, the cables and signal conductors are changed in distance between them, which results in undesired change in the electrical transmission properties. Further, signal conductors of different balanced transmission cables are not shielded to each other by removing the braided metal shields so that cross-talk is often caused.
It is therefore an object of the present invention to provide a cable connector which can resolve the problems described above.
This invention is applicable to a cable connector connectable to at least two balanced transmission cables each of which comprises a pair of signal conductors insulated from each other, and an electrical shield electrically insulated from and surrounding the pair of signal conductors. According to this invention, the cable connector comprises a first module and a second module which is combined with the first module. The first module comprises a first insulator and a ground portion electrically connectable to the electrical shields. The first insulator holds the ground portion and is provided with separator accommodation slits. The first insulator is further provided with cable receiving portions each of which is arranged between the respective neighboring separator accommodation slits and is able to hold one of the balanced transmission cables. The second module comprises at least two pairs of signal contacts connectable to the respective pairs of the signal conductors, ground contacts insulated from the signal contacts, separators physically and electrically connected to the ground contacts, and a second insulator holding the ground contacts and the signal contacts. The separators project from the second insulator. Under a combined state of the first and the second modules, the separators are fitted into the respective separator accommodation slits and are electrically connected to the ground portion.
According to an aspect, the first insulator has a first front end and a first rear end in a first direction. Each of the cable receiving portions extends in the first direction from the first rear end towards the first front end and is provided with a pair of positioning holes which are formed in the first front end and serve to position the corresponding pair of signal conductors. The signal contacts are arranged in correspondence with the respective positioning holes.
According to another aspect, the ground portion is comprised of at least two ground plates spaced from each other. Each of the separator accommodation slits is laid on a plane intersecting the ground plates, and each of the cable receiving portions is arranged between the ground plates. Under the combined state, the separators and the ground plates define enclosures for surrounding end portions of the respective balanced transmission cables.
According to another aspect, each of the pairs of the positioning holes are arranged on one and the same imaginary plane extending in the first and the third directions. The signal contacts constituting one pair are arranged in line with the third direction and each pair of the signal contacts is arranged between two pairs of the ground contacts in the second direction.
Further objects, features and advantages of the present invention are comprehensible from the following description of embodiments of the invention in connection with figures attached hereto.